Boots has fallen foul of the ad watchdog for an online ad that based its claims about a dietary product on a study that focused "inappropriately on obese subjects".

Boots has been told it must adapt advertising for its ‘carb control’ product after the Advertising Standards Authority (ASA) received a complaint saying claims that the product could reduce carbohydrate absorption by up to 66% and reduce the amount of carbohydrates digested and absorbed by the body, were misleading.

The health and beauty retailer defended itself by supplying two research papers that it believed backed up the claims it made.

However, the ASA deemed the evidence provided was not sufficient to support the claims being made about the weight management properties of the product.

The ad watchdog objected to one of the pieces of research focusing on 40 volunteers who were all obese.

It pointed out that its CAP Code prohibits ads targeting obese people and it considered the results could not be extrapolated to people who were overweight, but not obese.

The other piece of research was disregarded because the results were based on the drug being taken in powder form with four slices of bread, whereas ‘carb control’ is taken in tablet form.

However, when a more conventionally balanced meal was eaten, effectiveness of the drug fell to just 41% rather than the advertised 66%.

In a statement Boots said: "As a responsible healthcare retailer we are committed to providing our customers with accurate and factually correct information about the products we sell. We continually review our products and had already taken the decision to change the composition and the claims for Boots Pharmaceuticals Carb Control prior to the ASA investigation and ruling.

"The product is manufactured by another supplier to a different product specification and the claims made on boots.com are in line with the new product specification and formulation. At Boots UK we want to ensure we provide customers who shop with us the best possible range of products and services and if customers have any questions around which weight management products are suitable for their needs they can speak to one of our pharmacists."

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